Laminate and packaging container

Abstract

To provide a laminate excellent in interlayer adhesion with a vapor-deposited film, as well as having high gas barrier properties.SOLUTION: A laminate at least includes a substrate, a vapor-deposited film and a sealant layer. The sealant layer includes a surface resin layer and a polyethylene resin layer. The substrate is composed of a polyethylene resin. The surface resin layer of the sealant layer includes a resin material with a melting point 150°C or higher. The vapor-deposited film is disposed on the surface resin layer of the sealant layer.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a laminate and a packaging container.

[0002] Conventionally, resin films made of polyester resins such as polyethylene terephthalate (hereinafter also referred to as polyester films) have been used to produce packaging containers because they are excellent in mechanical properties, chemical stability, heat resistance, and transparency, as well as inexpensive.

[0003] Such a polyester film is used as a substrate, and is usually laminated with a polyethylene film, which is a sealant layer, to form a laminate, which is then formed into a packaging container.

[0004] The packaging container obtained by forming a laminate of the above-mentioned different resin films, i.e., a polyester film and a polyethylene film, is difficult to separate into its individual layers, and the packaging container collected after use is not suitable for recycling, and is not actively recycled.

[0005] In light of this current situation, and with the aim of improving the recyclability of packaging containers, studies are being conducted on the production of packaging containers using laminates made of the same material (mono-material packaging containers) by using stretched polyethylene film (stretched polyethylene film) as the base material instead of polyester film. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Publication No. 2005-053223 Summary of the Invention [Problem to be solved by the invention]

[0007] Recently, the present inventors attempted to form a vapor-deposited film on the surface of the polyethylene film of the sealant layer in order to compensate for the reduced gas barrier property that results from changing the substrate from a polyester film to a stretched polyethylene film. However, they discovered a new problem in that the adhesion between the polyethylene film and the vapor-deposited film was insufficient, making it impossible to obtain satisfactory gas barrier properties.

[0008] Then, surprisingly, the inventors discovered that by providing a surface resin layer containing a resin material having a melting point of 150°C or higher on the surface of a polyethylene film, the adhesion of a vapor-deposited film formed on the surface resin layer is improved, and as a result, the gas barrier properties are significantly improved, thereby solving the above-mentioned problems.

[0009] The present invention has been made based on such findings, and the problem to be solved by the present invention is to provide a laminate that can be suitably used as a laminate for producing mono-material packaging containers, that can significantly improve the adhesion between the layers and the vapor-deposited film, and that can achieve favorable gas barrier properties.

[0010] A further object of the present invention is to provide a packaging container comprising the laminate. [Means for solving the problem]

[0011] The laminate of the present invention includes at least a substrate, a vapor-deposited film, and a sealant layer, the sealant layer comprises a surface resin layer and a polyethylene resin layer, The substrate is made of a polyethylene resin, the surface resin layer of the sealant layer contains a resin material having a melting point of 150° C. or higher, The vapor-deposited film is provided on a surface resin layer of the sealant layer.

[0012] In one embodiment, the surface resin layer contains a resin material having a melting point of 150° C. or higher and 265° C. or lower.

[0013] In one embodiment, the difference in melting point between the polyethylene resin and the resin material contained in the surface resin layer and having a melting point of 150°C or higher is 20 to 80°C.

[0014] In one embodiment, the resin material of the surface resin layer is made of a polymer having a polar group.

[0015] In one embodiment, the resin material of the surface resin layer is one or more resin materials selected from ethylene-vinyl alcohol copolymer, polyvinyl alcohol, polyester, nylon 6, nylon 6,6, nylon 6-nylon 6,6 copolymer, MXD nylon, and amorphous nylon.

[0016] In one embodiment, the polyethylene resin layer of the sealant layer has a multi-layer structure.

[0017] In one embodiment, the polyethylene resin layer of the sealant layer comprises at least one layer comprising a compatibilizer.

[0018] In one embodiment, the surface resin layer is provided so as to be in contact with a layer containing a compatibilizer of the polyethylene resin layer.

[0019] In one embodiment, the laminate of the present invention further comprises a barrier coat layer provided on the vapor-deposited film.

[0020] In one embodiment, the laminate of the present invention is used in a packaging container.

[0021] In one embodiment, the content of the polyethylene resin in the entire laminate is 80 mass % or more.

[0022] The packaging container of the present invention is characterized by comprising the above-mentioned laminate.

[0023] In one embodiment, the packaging container is a packaging bag. Effect of the Invention

[0024] According to the present invention, it is possible to provide a laminate which can be suitably used as a laminate for producing a mono-material packaging container, which can significantly improve the interlayer adhesion with a vapor-deposited film, and which can achieve favorable gas barrier properties. Furthermore, according to the present invention, a packaging container including the laminate can be provided. [Brief description of the drawings]

[0025] [Figure 1] 1 is a schematic cross-sectional view showing one embodiment of a laminate of the present invention. [Diagram 2] 1 is a schematic cross-sectional view showing one embodiment of a laminate of the present invention. [Diagram 3] FIG. 1 is a schematic cross-sectional view illustrating one embodiment of a deposition apparatus. [Figure 4] FIG. 1 is a schematic cross-sectional view illustrating one embodiment of a deposition apparatus. [Diagram 5] 1 is a front view showing one embodiment of a packaging container of the present invention. [Figure 6] 1 is a perspective view showing one embodiment of a packaging container of the present invention. [Figure 7] 1 is a front view showing one embodiment of a packaging container of the present invention. [Figure 8] 8 is a cross-sectional view of FIG. 7 taken along line aa. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] (Laminate) As shown in FIG. 1, a laminate 10 of the present invention comprises a substrate 11, a vapor-deposited film 12, and a sealant layer 13, and the sealant layer 13 comprises a surface resin layer 14 and a polyethylene resin layer 15. The polyethylene resin layer of the sealant layer and the substrate of the laminate are made of the same resin, i.e., polyethylene resin. A laminate having such a configuration can be suitably used as a laminate for producing a mono-material packaging container. Furthermore, the laminate of the present invention has significantly improved interlayer adhesion between the sealant layer and the vapor-deposited film, and has extremely high gas barrier properties.

[0027] The content of the polyethylene resin relative to the total amount of solids contained in the laminate is preferably 80% by mass or more, and more preferably 90% by mass or more, which makes the laminate suitable for use in producing mono-material packaging containers.

[0028] In one embodiment, the sealant layer 13 may further include an adhesive resin layer 16 between the surface resin layer 14 and the polyethylene resin layer 15, as shown in FIG.

[0029] Furthermore, in one embodiment, the laminate 10 of the present invention includes a barrier coat layer adjacent to the deposited film 12 (not shown).

[0030] Furthermore, in one embodiment, the laminate 10 of the present invention includes an adhesive layer (not shown) between any of the layers, for example, between the deposited film 12 and the sealant layer 13 .

[0031] Each layer of the laminate of the present invention will be described below.

[0032] (base material) The substrate is made of the same resin as the polyethylene resin layer of the sealant layer, i.e., a polyethylene resin. A laminate having such a configuration can be suitably used as a laminate for producing a mono-material packaging container. As the polyethylene resin, high density polyethylene resin (HDPE), medium density polyethylene resin (MDPE), low density polyethylene resin (LDPE), linear low density polyethylene resin (LLDPE) and very low density polyethylene resin (VLDPE) can be used. Moreover, as the polyethylene resin, a copolymer of ethylene and another monomer can also be used. Furthermore, as the polyethylene resin, a biomass-derived polyethylene resin or a mechanically recycled or chemically recycled polyethylene resin can also be used.

[0033] Here, the high density polyethylene resin has a density of 0.945 g / cm 3 The polyethylene resins used are those with a density of 0.925 g / cm or more. Medium density polyethylene resins are those with a density of 0.925 g / cm or more. 3 More than 0.945g / cm 3 A polyethylene resin having a density of less than 0.900 g / cm can be used. 3 More than 0.925g / cm 3 A polyethylene resin having a density of less than 0.900 g / cm can be used. As a linear low-density polyethylene resin, a polyethylene resin having a density of less than 0.900 g / cm can be used. 3 More than 0.925g / cm 3 For ultra-low density polyethylene resin, a polyethylene resin with a density of 0.900 g / cm3 or less can be used. 3 Polyethylene resins less than 100% may be used.

[0034] The content of the polyethylene resin in the substrate is preferably 80% by mass or more, and more preferably 90% by mass or more, which makes it possible to obtain a laminate that can be suitably used for producing mono-material packaging containers.

[0035] As long as the characteristics of the present invention are not impaired, the substrate may contain a resin material other than polyethylene resin, and examples of the resin material include polyolefin resins such as polypropylene resin, (meth)acrylic resins, vinyl resins, cellulose resins, polyamide resins, polyester resins, and ionomer resins. From the viewpoint of recyclability, it is particularly preferable that the base material does not contain any resin other than polyethylene resin.

[0036] The base material may contain the above-mentioned additives as long as the characteristics of the present invention are not impaired.

[0037] The substrate may have a single-layer structure or a multi-layer structure.

[0038] In a substrate having a multi-layer structure, the polyethylene resin constituting each layer may have a different density, that is, the substrate may have a density gradient. By providing a density gradient in the substrate, the strength, heat resistance and stretchability are significantly improved.

[0039] In a substrate with a density gradient, if the density difference between the layers is large, delamination may occur at the interface. Therefore, the density difference between the layers should be less than 0.04 g / cm 3 It is preferable that the concentration is 0.02 g / cm or less. 3 It is even more preferable that:

[0040] The following are examples of the substrate having a density gradient. However, the configuration of the substrate is not limited to these.

[0041] In one embodiment, the substrate having a density gradient is made up of three layers: a layer containing a high density polyethylene resin, a layer containing a medium density polyethylene resin, and a layer containing a high density polyethylene resin. By forming the substrate into a three-layer structure having the above-mentioned density gradient, the strength, heat resistance, and stretchability are significantly improved, and the substrate can be effectively prevented from curling.

[0042] In one embodiment, the substrate having a density gradient is composed of five layers: a layer containing high-density polyethylene, a layer containing medium-density polyethylene resin, a layer containing at least one of a low-density polyethylene resin and a linear low-density polyethylene resin, a layer containing medium-density polyethylene resin, and a layer containing a high-density polyethylene resin. By forming the substrate into a five-layer structure having the above-mentioned density gradient, the strength, heat resistance, and stretchability are significantly improved, and the substrate can be effectively prevented from curling. A substrate having such a structure can be stably produced by an inflation method as described below. Specifically, a high-density polyethylene resin, a medium-density polyethylene resin, and at least one of a low-density polyethylene resin and a linear low-density polyethylene resin are co-extruded from the outside into a tubular shape, Next, the layers containing at least one of the low density polyethylene resin and the linear low density polyethylene resin are pressure-bonded together using a rubber roll or the like to produce a laminate. By using such a method, the number of defective products during manufacturing can be significantly reduced, and ultimately, production efficiency can be improved.

[0043] In one embodiment, the substrate having a density gradient is composed of seven layers: a layer containing a high-density polyethylene resin, a layer containing a blend resin of high-density polyethylene resin and medium-density polyethylene resin, a layer containing at least one of a low-density polyethylene resin and a linear low-density polyethylene resin, a layer containing a blend resin of high-density polyethylene resin and medium-density polyethylene resin, and a layer containing a high-density polyethylene resin. By forming the substrate into a five-layer structure having the above-mentioned density gradient, the strength, heat resistance and stretchability are significantly improved. In addition, the substrate can be effectively prevented from curling. Furthermore, the substrate can be effectively prevented from delamination. Moreover, a substrate having such a structure can be stably produced by the inflation method described above.

[0044] In one embodiment, the substrate is subjected to a stretching treatment, and the stretching treatment may be uniaxial stretching or biaxial stretching. The stretching ratio of the substrate in the machine direction (MD direction) and the transverse direction (TD direction) is preferably 2 times or more and 15 times or less, and more preferably 5 times or more and 13 times or less. By setting the stretching ratio at 2 times or more, the strength and heat resistance of the substrate can be further improved, and the printability of the substrate can also be improved. From the viewpoint of the breaking limit of the substrate, the stretching ratio is preferably 15 times or less.

[0045] The substrate may have a printed layer on its surface. The image formed on the printed layer is not particularly limited, and may represent characters, patterns, symbols, combinations of these, and the like. The printing layer can be formed using ink derived from biomass, which reduces the environmental impact. The method for forming the printed layer is not particularly limited, and examples of the method include conventionally known printing methods such as gravure printing, offset printing, and flexographic printing.

[0046] In addition, the substrate is preferably subjected to a surface treatment, which can improve adhesion to adjacent layers. The method of surface treatment is not particularly limited, and examples thereof include physical treatments such as corona discharge treatment, ozone treatment, low-temperature plasma treatment using oxygen gas and / or nitrogen gas, and glow discharge treatment, as well as chemical treatments such as oxidation treatment using chemicals. Furthermore, an anchor coat layer may be formed on the surface of the substrate using a conventionally known anchor coat agent.

[0047] The thickness of the substrate is preferably 9 μm or more and 50 μm or less, and more preferably 12 μm or more and 30 μm or less. By setting the thickness of the substrate within the above numerical range, the printability, strength, and heat resistance of the substrate can be further improved.

[0048] (evaporated film) The laminate of the present invention has a vapor-deposited film between the substrate and the sealant layer and on the surface resin layer, which can improve the gas barrier properties, specifically the oxygen barrier properties and water vapor barrier properties. In addition, it is possible to suppress the weight loss of the contents filled in a packaging container produced using the laminate of the present invention.

[0049] The vapor-deposited film may be a vapor-deposited film of one or more inorganic substances or inorganic oxides such as silicon (Si), aluminum (Al), magnesium (Mg), calcium (Ca), potassium (K), tin (Sn), sodium (Na), boron (B), titanium (Ti), lead (Pb), zirconium (Zr), yttrium (Y), etc. The vapor-deposited film may be composed of two or more layers, and may be composed of the same material or different materials. Among the above, from the viewpoints of adhesion to the surface resin layer and gas barrier properties, the vapor-deposited film is preferably composed of aluminum, aluminum oxide (alumina) or silicon oxide (silica).

[0050] The surface of the deposited film is preferably subjected to the above-mentioned surface treatment, which can improve adhesion to adjacent layers.

[0051] The thickness of the evaporated film is preferably 1 nm or more and 150 nm or less, more preferably 5 nm or more and 60 nm or less, and even more preferably 10 nm or more and 40 nm or less. By making the thickness of the vapor-deposited film 1 nm or more, the oxygen barrier property and water vapor barrier property of the laminate can be further improved. Moreover, by setting the thickness of the vapor-deposited film to 150 nm or less, a laminate that can be suitably used for producing mono-material packaging containers can be obtained, and further, the occurrence of cracks in the vapor-deposited film can be prevented.

[0052] As an apparatus used in the method for forming a vapor-deposited film by the PVD method, a plasma-assisted vacuum film-forming apparatus can be used. An embodiment of a method for forming a vapor-deposited film using a plasma-assisted vacuum film-forming apparatus will be described below. In one embodiment, the vacuum deposition apparatus includes a vacuum container A, a sealant layer 10, an unwinding section B, a deposition drum C, a winding section D, a transport roll E, an evaporation source F, a reactive gas supply section G, an adhesion-proof box H, a deposition material I, and a plasma gun J, as shown in Figures 3 and 4. 3 is a schematic cross-sectional view of the vacuum film-forming apparatus in the XZ plane, and FIG. 4 is a schematic cross-sectional view of the vacuum film-forming apparatus in the XY plane. 3, the sealant layer 10 wound around the film-forming drum C is placed with its surface resin layer surface facing downward in the upper part of the vacuum container A, and an electrically grounded deposition-protection box H is placed below the film-forming drum C in the vacuum container A. An evaporation source F is placed on the bottom surface of the deposition-protection box H. The film-forming drum C is placed in the vacuum container A so that the surface resin layer surface of the sealant layer 10 wound around the film-forming drum C is located at a position facing the upper surface of the evaporation source F with a certain gap therebetween. In addition, transport rolls E are disposed between the unwinding section B and the film-forming drum C, and between the film-forming drum C and the winding section D. The vacuum vessel is connected to a vacuum pump (not shown). The evaporation source F is for holding the evaporation material I, and is equipped with a heating device (not shown). The reactive gas supply unit G is a portion that supplies a reactive gas (such as oxygen, nitrogen, helium, argon, and a mixture of these gases) that reacts with the evaporated deposition material. The vapor deposition material I is heated and evaporated from the evaporation source F and directed toward the surface resin layer of the sealant layer 10, and at the same time, plasma is also directed toward the surface resin layer from the plasma gun J, forming a vapor deposition film. The details of this formation method are disclosed in JP 2011-214089 A.

[0053] As the plasma generating device used in the plasma chemical vapor deposition method, a device generating high frequency plasma, pulse wave plasma, microwave plasma, etc. may be used. Also, a device having two or more film formation chambers may be used. The device is preferably equipped with a vacuum pump so that each film formation chamber can be kept under vacuum. The degree of vacuum in each deposition chamber was 1×10 to 1×10 -6 Pa is preferred. An embodiment of a method for forming a vapor-deposited film using a plasma generating device will be described below. First, the sealant layer is sent into the film-forming chamber and transported at a predetermined speed onto the cooling electrode drum via an auxiliary roll. Next, a mixed gas composition containing a film-forming monomer gas containing an inorganic oxide, oxygen gas, an inert gas, etc. is supplied from the gas supply device into the film-forming chamber, and plasma is generated on the surface resin layer by glow discharge, which is then irradiated to form a vapor-deposited film containing an inorganic oxide on the surface resin layer. The details of this formation method are disclosed in JP2012-076292A.

[0054] As an apparatus used in the method for forming a vapor-deposited film, a continuous vapor-deposited film-forming apparatus equipped with a plasma pretreatment chamber and a film-forming chamber can be used. An embodiment of a method for forming a vapor-deposited film using the apparatus will be described below. First, in the plasma pretreatment chamber, plasma is irradiated onto the surface resin layer of the sealant layer from a plasma supply nozzle, and then, in the film formation chamber, a deposition film is formed on the plasma-treated surface resin layer. Details of this formation method are disclosed in International Publication WO2019 / 087960.

[0055] (Sealant layer) The sealant layer includes a surface resin layer and a polyethylene resin layer, and in one embodiment, an adhesive resin layer is provided between the surface resin layer and the polyethylene resin layer.

[0056] The ratio of the thickness of the surface resin layer to the total thickness of the sealant layer is preferably 2% or more and 20% or less, and more preferably 4% or more and 15% or less. By making the ratio of the thickness of the surface resin layer to the total thickness of the sealant layer 2% or more, the adhesion of the vapor-deposited film can be further improved, and the gas barrier properties can be further improved. In addition, by setting the ratio of the thickness of the surface resin layer to the total thickness of the sealant layer to 20% or less, a laminate that can be suitably used for producing mono-material packaging containers can be obtained. Furthermore, the film-forming property and processability of the sealant layer can be further improved.

[0057] (Polyethylene resin layer) The polyethylene resin layer is made of a polyethylene resin. As the polyethylene resin, high density polyethylene resin (HDPE), medium density polyethylene resin (MDPE), low density polyethylene resin (LDPE), linear low density polyethylene resin (LLDPE) and very low density polyethylene resin (VLDPE) can be used. Moreover, as the polyethylene resin, a copolymer of ethylene and another monomer can also be used. Furthermore, as the polyethylene resin, a biomass-derived polyethylene resin or a mechanically recycled or chemically recycled polyethylene resin can also be used.

[0058] The content of the polyethylene resin in the polyethylene resin layer is preferably 70% by mass or more, and more preferably 80% by mass or more, which allows the laminate to be more suitably used for producing a mono-material packaging container.

[0059] In one embodiment, the polyethylene resin layer may include at least one layer including a compatibilizer. By including a compatibilizer in the polyethylene resin layer, when a packaging container made using the laminate is heated and melted for recycling, the resin material having a melting point of 150° C. or more contained in the surface resin layer and the polyethylene resin contained in the polyethylene resin layer are uniformly mixed together, which effectively prevents the physical properties from deteriorating. Also, the transparency is effectively prevented from deteriorating. In addition, when the polyethylene resin layer has a multi-layer structure, the compatibilizer is preferably contained in a layer in contact with the surface resin layer of the polyethylene resin layer. By containing the compatibilizer in the layer in contact with the surface resin layer of the polyethylene resin layer, the above-mentioned effect can be further improved.

[0060] The compatibilizer may be appropriately selected from conventionally known ones and used. From the viewpoint of recyclability, however, unsaturated carboxylic acid modified polyolefin resins are preferred, and among them, maleic anhydride modified polyethylene resins are more preferred.

[0061] The content of the compatibilizer in the layer containing the compatibilizer is preferably from 5% by mass to 30% by mass. By setting the content of the compatibilizer in the polyethylene resin layer to 5% by mass or more, the above-mentioned effects can be further improved. By setting the content of the compatibilizer in the polyethylene resin layer to 30% by mass or less, the strength and heat resistance of the substrate can be improved.

[0062] As long as the characteristics of the present invention are not impaired, the polyethylene resin layer may contain a resin material other than polyethylene resin, for example, a polyolefin resin such as a polypropylene resin, a (meth)acrylic resin, a vinyl resin, a cellulose resin, a polyamide resin, a polyester resin, and an ionomer resin. From the viewpoint of recyclability, it is particularly preferable that the polyethylene resin layer does not contain any resin other than polyethylene resin.

[0063] Furthermore, to the extent that the characteristics of the present invention are not impaired, the polyethylene resin layer may contain additives, such as crosslinking agents, antioxidants, antiblocking agents, slip agents, UV absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, and modifying resins.

[0064] The polyethylene resin layer may have a single-layer structure or a multi-layer structure.

[0065] In the polyethylene resin layer having a multi-layer structure, the density of the polyethylene resin constituting each layer may be different, that is, the polyethylene resin layer may have a density gradient. By providing a density gradient in the polyethylene resin layer, the strength, heat resistance and stretchability are significantly improved.

[0066] In a polyethylene resin layer having a density gradient, if the density difference between the layers is large, delamination may occur at the interface. Therefore, the density difference between the layers is set to 0.04 g / cm 3 It is preferable that the concentration is 0.02 g / cm or less. 3 It is even more preferable that:

[0067] The following are examples of the polyethylene resin layer having a density gradient, but the configuration of the polyethylene resin layer is not limited to these.

[0068] In one embodiment, the polyethylene resin layer having a density gradient is composed of three layers: a layer containing a high density polyethylene resin, a layer containing a medium density polyethylene resin, and a layer containing a high density polyethylene resin. By forming the polyethylene resin layer into a three-layer structure having the density gradient as described above, the strength, heat resistance and stretchability are significantly improved, and the occurrence of curling in the sealant layer can be effectively prevented.

[0069] In one embodiment, the polyethylene resin layer having a density gradient is composed of five layers: a layer containing high-density polyethylene, a layer containing medium-density polyethylene resin, a layer containing at least one of a low-density polyethylene resin and a linear low-density polyethylene resin, a layer containing medium-density polyethylene resin, and a layer containing a high-density polyethylene resin. By forming the polyethylene resin layer into a five-layer structure having the density gradient as described above, the strength, heat resistance and stretchability are significantly improved, and the occurrence of curling in the sealant layer can be effectively prevented. The polyethylene resin layer having such a structure can be stably produced by the inflation method described above.

[0070] In one embodiment, the polyethylene resin layer having a density gradient is composed of seven layers: a layer containing a high-density polyethylene resin, a layer containing a blended resin of high-density polyethylene resin and medium-density polyethylene resin, a layer containing at least one of a low-density polyethylene resin and a linear low-density polyethylene resin, a layer containing a blended resin of high-density polyethylene resin and medium-density polyethylene resin, and a layer containing a high-density polyethylene resin. By forming the polyethylene resin layer into a five-layer structure having the density gradient as described above, the strength, heat resistance and stretchability are significantly improved. In addition, curling in the sealant layer can be effectively prevented. Furthermore, delamination in the sealant layer can be effectively prevented. Moreover, the polyethylene resin layer having such a structure can be stably produced by the inflation method described above.

[0071] The thickness of the polyethylene resin layer is preferably 10 μm or more and 50 μm or less, and more preferably 10 μm or more and 40 μm or less. By making the thickness of the polyethylene resin layer 10 μm or more, the strength and heat resistance of the sealant layer can be further improved. Furthermore, by setting the thickness of the polyethylene resin layer to 50 μm or less, the film-forming properties and processability of the sealant layer can be further improved.

[0072] The polyethylene resin layer may have a printed layer on its surface. The image formed on the printed layer is not particularly limited, and may be a letter, a pattern, a symbol, or a combination thereof. The printing layer can be formed using ink derived from biomass, which reduces the environmental impact. The method for forming the printed layer is not particularly limited, and examples of the method include conventionally known printing methods such as gravure printing, offset printing, and flexographic printing.

[0073] (Surface resin layer) The sealant layer of the laminate comprises a surface protective layer on a polyethylene resin layer, the surface protective layer containing a resin material having a melting point of 150° C. or higher (hereinafter also referred to as a high melting point resin material). A highly adhesive vapor-deposited film can be formed on the surface resin layer, improving the gas barrier properties. Furthermore, packaging containers produced using the laminate of the present invention have high laminate strength (heat sealability).

[0074] The melting point of the high melting point resin material is more preferably 160° C. or higher. By setting the melting point of the high melting point resin material to 160° C. or higher, the adhesion of the vapor-deposited film can be improved, the gas barrier properties can be improved, and the laminate strength of the packaging container produced from this laminate can be improved.

[0075] The melting point of the high-melting-point resin material is preferably 265° C. or less, more preferably 260° C. or less, and even more preferably 250° C. or less. By setting the melting point of the high-melting-point resin material to 265° C. or less, the film-forming properties of the sealant layer can be improved.

[0076] The difference between the melting point of the high melting point resin material contained in the surface resin layer and the melting point of the polyethylene contained in the polyethylene resin layer is preferably 20 to 80°C, and more preferably 20 to 60°C. By setting the difference between the melting point of the high melting point resin material contained in the surface resin layer and the melting point of the polyethylene contained in the polyethylene resin layer to 20° C. or more, the adhesion of the vapor-deposited film can be improved, the gas barrier properties of the substrate on which the vapor-deposited film is formed can be improved, and the laminate strength of the packaging container produced from this laminate can be improved. In addition, by making the difference between the melting point of the high melting point resin material contained in the surface resin layer and the melting point of the polyethylene contained in the polyethylene resin layer 80° C. or less, the film formability of the sealant layer can be further improved.

[0077] In one embodiment, the high melting point resin material is made of a polymer having a polar group. By making the high melting point resin material a polymer having a polar group, the adhesion to the vapor-deposited film can be further improved.

[0078] In the present invention, the polar group refers to a group containing one or more heteroatoms, and examples thereof include an ester group, an epoxy group, a hydroxyl group, an amino group, an amide group, a carboxyl group, a carbonyl group, a carboxylic anhydride group, a sulfone group, a thiol group, and a halogen group. Among these, from the viewpoint of the laminate strength of the packaging container, a hydroxyl group, an ester group, an amino group, an amide group, a carboxyl group and a carbonyl group are preferred, and a hydroxyl group is more preferred.

[0079] Examples of high melting point resin materials include vinyl resins, polyamides, polyimides, polyesters, (meth)acrylic resins, cellulose resins, polyolefin resins, and ionomer resins.

[0080] In the present invention, a resin material having a melting point of 150°C or higher and having a polar group is particularly preferred, and amide resins such as ethylene-vinyl alcohol copolymers, polyvinyl alcohol, nylon 6, nylon 6,6, nylon 6-nylon 6,6 copolymers, MXD nylon, and amorphous nylon are preferred, with ethylene-vinyl alcohol copolymers and amide resins being particularly preferred. By using such a resin material, the adhesion of the evaporated film formed on the surface resin layer can be significantly improved, and the gas barrier properties can be effectively improved.

[0081] The content of the high melting point resin material in the surface resin layer is preferably 70% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more. By making the content of the high melting point resin material in the surface resin layer 70% by mass or more, the adhesion of the vapor deposition film formed on the surface resin layer can be significantly improved, and the gas barrier property of the sealant layer on which the vapor deposition film is formed can be effectively improved.

[0082] As long as the characteristics of the present invention are not impaired, the surface resin layer may contain a resin material other than the high melting point resin material. From the viewpoint of adhesion to the evaporated film, it is preferable that the surface resin layer does not contain any resin material other than the high melting point resin material.

[0083] Furthermore, within the scope of not impairing the characteristics of the present invention, the surface resin layer may contain additives, such as crosslinking agents, antioxidants, antiblocking agents, slip agents, UV absorbers, light stabilizers, fillers, reinforcing agents, antistatic agents, pigments, and modifying resins.

[0084] The thickness of the surface resin layer is preferably 0.1 μm or more and 5 μm or less, and more preferably 0.1 μm or more and 4 μm or less. By making the thickness of the surface resin layer 0.1 μm or more, the adhesion of the vapor-deposited film can be improved, and the gas barrier property of the sealant layer on which the vapor-deposited film is formed can be improved. In addition, when a sealant layer is laminated, the adhesion with the sealant layer can be improved, and the laminate strength of the packaging container made from this laminate can be improved. Moreover, by setting the thickness of the surface resin layer to 5 μm or less, it is possible to provide a sealant layer that can be suitably used for producing mono-material packaging containers, and further improve the film-forming properties and processability of the sealant layer.

[0085] The surface resin layer may be subjected to a surface treatment, which can improve the adhesion to the adjacent layers. The method of surface treatment is not particularly limited, and examples thereof include physical treatments such as corona discharge treatment, ozone treatment, low-temperature plasma treatment using oxygen gas and / or nitrogen gas, and glow discharge treatment, as well as chemical treatments such as oxidation treatment using chemicals.

[0086] (adhesive resin layer) In one embodiment, the sealant layer may include an adhesive resin layer between the polyethylene resin layer and the surface resin layer, thereby improving the adhesion between these layers.

[0087] The adhesive resin layer can be formed by using an adhesive resin such as polyether, polyester, silicone resin, epoxy resin, polyurethane, vinyl resin, phenol resin, and polyolefin. Among the above, polyolefins and acid-modified products thereof are preferred, and polyethylene and acid-modified products thereof are particularly preferred, because the laminate can be made into a structure more suitable for mono-material packaging containers. As the adhesive polyethylene, commercially available products can be used, for example, the Admer series manufactured by Mitsui Chemicals, Inc. can be used.

[0088] In one embodiment, the sealant layer is a co-extrusion film, and can be produced by film formation using a T-die method, an inflation method, or the like.

[0089] From the viewpoint of heat sealability, the sealant layer is preferably composed of an unstretched film. When the laminate is used to produce a laminate tube or the like, the laminate further comprises a sealant layer (not shown) on the surface of the substrate on which the vapor-deposited film is not formed.

[0090] (Barrier coat layer) The laminate may further include a barrier coat layer on the vapor-deposited film, thereby improving the oxygen barrier property and water vapor barrier property of the laminate.

[0091] In one embodiment, the barrier coat layer comprises a gas barrier resin such as ethylene-vinyl alcohol copolymer (EVOH), polyvinyl alcohol, polyacrylonitrile, polyamide resins such as nylon 6, nylon 6,6 and polymetaxylylene adipamide (MXD6), polyester resins, polyurethane resins, and (meth)acrylic resins.

[0092] The content of the gas barrier resin in the barrier coat layer is preferably 50% by mass or more and 95% by mass or less, and more preferably 75% by mass or more and 90% by mass or less. By making the content of the gas barrier resin in the barrier coat layer 50% by mass or more, the oxygen barrier property and water vapor barrier property can be further improved.

[0093] The thickness of the barrier coat layer is preferably 0.01 μm or more and 10 μm or less, and more preferably 0.1 μm or more and 5 μm or less. By making the thickness of the barrier coat layer 0.01 μm or more, the oxygen barrier property and water vapor barrier property of the laminate can be further improved. By making the thickness of the barrier coat layer 10 μm or less, the processability of the laminate can be improved. In addition, the recyclability of a packaging container made using a laminate of a substrate and a sealant layer made of a polyethylene resin can be improved.

[0094] The barrier coat layer can be formed by dissolving or dispersing the above-mentioned material in water or a suitable solvent, applying the solution, and drying the solution. Alternatively, the barrier coat layer can be formed by applying a commercially available barrier coat agent and drying the solution.

[0095] In another embodiment, the barrier coat layer is a gas barrier coating film containing at least one resin composition such as a hydrolysate of a metal alkoxide or a hydrolyzed condensate of a metal alkoxide obtained by polycondensing a mixture of a metal alkoxide and a water-soluble polymer by a sol-gel method in the presence of a sol-gel catalyst, water, an organic solvent, etc. By providing such a barrier coat layer on the vapor-deposited film, the occurrence of cracks in the vapor-deposited film can be effectively prevented.

[0096] In one embodiment, the metal alkoxide is represented by the following general formula: R 1 n M(OR 2 ) m (In the formula, R 1 , R 2 each represents an organic group having 1 to 8 carbon atoms, M represents a metal atom, n represents an integer of 0 or more, m represents an integer of 1 or more, and n+m represents the atomic valence of M.

[0097] As the metal atom M, for example, silicon, zirconium, titanium, aluminum, etc. can be used. Also, R 1 and R 2Examples of the organic group represented by the formula (I) include alkyl groups such as a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, and an i-butyl group.

[0098] Examples of metal alkoxides that satisfy the above general formula include tetramethoxysilane (Si(OCH3)4), tetraethoxysilane (mass %) Si(OC2H5)4), tetrapropoxysilane (Si(OC3H7)4), and tetrabutoxysilane (Si(OC4H9)4).

[0099] It is also preferable to use a silane coupling agent together with the metal alkoxide. As the silane coupling agent, a known organoalkoxysilane containing an organic reactive group can be used.

[0100] As the water-soluble polymer, polyvinyl alcohol and an ethylene-vinyl alcohol copolymer are preferred, and from the viewpoints of oxygen barrier properties, water vapor barrier properties, water resistance and weather resistance, it is preferred to use these in combination.

[0101] The thickness of the gas barrier coating film is preferably from 0.01 μm to 10 μm, and more preferably from 0.1 μm to 5 μm. By making the thickness of the gas barrier coating film 0.01 μm or more, the oxygen barrier property and water vapor barrier property of the laminate can be improved, and the occurrence of cracks in the vapor-deposited film can be prevented. By setting the thickness of the gas barrier coating film to 10 μm or less, it is possible to obtain a laminate that can be suitably used for producing mono-material packaging containers.

[0102] The gas barrier coating film can be formed by applying a composition containing the above-mentioned materials by a conventionally known means such as roll coating using a gravure roll coater or the like, spray coating, spin coating, dipping, brushing, bar coding, or an applicator, and then polycondensing the composition by a sol-gel method. As the sol-gel catalyst, an acid or an amine compound is preferable.

[0103] The composition may further contain an acid, which is used as a catalyst in the sol-gel process, mainly for the hydrolysis of alkoxides, silane coupling agents, and the like. As the acid, mineral acids such as sulfuric acid, hydrochloric acid, nitric acid, etc., and organic acids such as acetic acid, tartaric acid, etc. can be used.

[0104] The composition may also contain an organic solvent, such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, or n-butanol.

[0105] Hereinafter, one embodiment of the method for forming a gas barrier coating film will be described. First, a composition is prepared by mixing a metal alkoxide, a water-soluble polymer, a sol-gel catalyst, water, an organic solvent, and optionally a silane coupling agent, etc. In the composition, a polycondensation reaction gradually proceeds. Next, the composition is applied onto the vapor-deposited film by the above-mentioned conventionally known method and dried. This drying process further advances the polycondensation reaction between the alkoxide and the water-soluble polymer (and the silane coupling agent, if the composition contains a silane coupling agent) to form a composite polymer layer. Finally, the gas barrier coating film can be formed by heating.

[0106] (Adhesive layer) The laminate of the present invention may have an adhesive layer between any of the layers, for example, between the vapor-deposited film and the sealant layer. The adhesive layer contains at least one adhesive, and may be a one-component curing type, a two-component curing type, or a non-curing type adhesive. The adhesive may be a solvent-free adhesive or a solvent-based adhesive, but from the viewpoint of environmental load, a solvent-free adhesive is preferably used. Examples of solvent-free adhesives include polyether adhesives, polyester adhesives, silicone adhesives, epoxy adhesives, and urethane adhesives, and among these, two-component curing urethane adhesives can be preferably used. Examples of the solvent-based adhesive include rubber-based adhesives, vinyl-based adhesives, silicone-based adhesives, epoxy-based adhesives, phenol-based adhesives, and olefin-based adhesives.

[0107] The thickness of the adhesive layer is preferably 1 μm or more and 15 μm or less, more preferably 3 μm or more and 10 μm or less. By making the thickness of the adhesive layer 1 μm or more, it is possible to improve the adhesion between the layers. In addition, by making the thickness of the adhesive layer 15 μm or less, it is possible to improve the recyclability of the packaging container produced using the barrier laminate of the present invention having a base material and a sealant layer composed of polyethylene.

[0108] (packaging container) The packaging container of the present invention is characterized by comprising the laminate. Examples of the packaging container include packaging products (packaging bags), lids, and laminate tubes.

[0109] Examples of packaging bags include packaging bags of various shapes, such as standing pouch type, side seal type, two-sided seal type, three-sided seal type, four-sided seal type, envelope seal type, grommet seal type (pillow seal type), pleated seal type, flat bottom seal type, square bottom seal type, and gusset type.

[0110] As shown in FIG. 5, the packaging container of the present invention is a packaging bag 20 made by bonding two laminates together (the shaded areas are the heat-sealed areas).

[0111] A packaging bag having the configuration shown in FIG. 5 can be produced by preparing two laminates each including a substrate and a vapor deposition film and a sealant layer provided on one side of the substrate, stacking the laminates with the sealant layers facing each other, and heat-sealing three sides.

[0112] In one embodiment, the packaging container of the present invention is a standing pouch-type packaging bag 30 (hereinafter simply referred to as a standing pouch 30) as shown in FIG. 6, and the standing pouch 30 has a body portion (side sheet) and a bottom portion (bottom sheet). The body (side sheet) of the standing pouch 30 is made of a laminate including at least a substrate, and a vapor-deposited film and a sealant layer provided on one side of the substrate. The bottom may also be made of a laminate including a substrate, and a deposition film and a sealant layer provided on one surface of the substrate. By using such a configuration, the gas barrier property of the standing pouch 30 can be further improved.

[0113] The body (side sheet) of a standing pouch 30 as shown in FIG. 6 can be formed by making a bag so that the sealant layer of a laminate comprising a substrate, a vapor deposition film and a sealant layer provided on one side of the substrate is the innermost layer. In another embodiment, two laminates each including a substrate and a vapor deposition film and a sealant layer provided on one surface of the substrate are prepared, and these are stacked together with the sealant layers facing each other, and two laminates folded in a V shape are inserted into both ends of the stacked laminate with the sealant layers facing outward, followed by heat sealing to form the body (side sheet) of the standing pouch 30. According to this production method, a standing pouch having a body with side gussets can be obtained. The bottom (bottom sheet) of the standing pouch 30 can be formed by inserting the laminate between the body (side sheets) of a bag and heat sealing it. More specifically, the laminate can be folded in a V shape so that the sealant layer is on the outside, inserted between the side sheets of a bag, and heat sealed.

[0114] The packaging container may also be provided with easy-opening means 41 as shown in FIG. As shown in FIG. 5, examples of the easy-to-open means 41 include a notch 42 which serves as a starting point for tearing, and a half-cut line 43 formed by laser processing or a cutter as a path for tearing.

[0115] The packaging container may be a stand-up pouch equipped with a dispensing nozzle part 51 as shown in FIG. From the viewpoint of ease of opening, the stand pouch 30 may have a curved portion 52 curved inward as shown in FIG. Additionally, cutouts 53 may be provided, such as those formed by a laser beam.

[0116] (Laminated tube) The laminate tube of the present invention is characterized by comprising the above-mentioned laminate, specifically, a laminate constituted by a laminate film provided with a sealant layer on both sides. The laminated tube of the present invention will be described below with reference to the drawings. Fig. 7 is a diagram showing a simplified configuration of a laminated tube 60, and Fig. 8 is a cross-sectional view taken along line aa in Fig. 7. As shown in Fig. 7, the laminated tube 60 is characterized in that it comprises a laminated tube body 61 having a head 62 and a body 63, and the body 63 is formed from the laminated body.

[0117] (head) The head portion 62 has a shoulder portion 64 connected to one end of the body portion 63 and a sampling port portion 65 connected to the shoulder portion 64. In one embodiment, the spout portion 65 also includes a thread 67 for screwing the cap 66 onto it.

[0118] In one embodiment, the head portion is made of a resin composition containing polyethylene, which can improve the recyclability of the tube container.

[0119] The method for producing the head is not particularly limited, and the head can be produced by a conventionally known method. For example, the head can be produced by a compression molding method or an injection molding method, and can be joined to the body.

[0120] (Torso) In the laminate tube body 61 of the present invention, the trunk portion 63 is connected to a shoulder portion 64 of the head portion 62 . The body 63 includes a welded portion 68 formed by rolling the laminate into a cylindrical shape, overlapping the heat-sealed layers, and heat-sealing the overlapped portion. The body 63 also includes a bottom seal 69 formed by heat sealing the opening of the rolled laminate.

[0121] (cap) The laminate tube 60 may be provided with a screw-type or plug-type cap 66 . The cap is removably attached to the extraction port of the head and serves to close the extraction port. The cap is made of a resin composition including a thermoplastic resin. From the viewpoint of recyclability, the thermoplastic resin is particularly preferably a polyethylene resin.

[0122] The contents filled in the packaging container are not particularly limited, and may be liquid, powder, or gel. In addition, the contents may be food or non-food. EXAMPLES

[0123] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0124] Example 1-1 Medium density polyethylene (Dow Chemical, Elite 5538, density: 0.941 g / cm 3A single layer of the polyester resin (melting point: 129° C.) was extruded by the inflation method and then stretched 5 times in the machine direction (MD direction) using a stretching device to produce a substrate with a thickness of 25 μm.

[0125] Ethylene-vinyl alcohol copolymer (Kuraray Co., Ltd., EVAL E171B, melting point: 165°C, density: 1.14g / cm 3 )and, Adhesive resin (Mitsui Chemicals, Inc., maleic anhydride modified polyethylene, Admer NF557, density: 0.920 g / cm 3 )and, Linear density polyethylene (Prime Polymer, SP1520, density 0.913, melting point 116°C) The mixture was co-extruded by a T-die method to obtain a sealant layer having a thickness of 40 μm. In the sealant layer thus obtained, the surface resin layer composed of ethylene-vinyl alcohol copolymer had a thickness of 2 μm, the adhesive resin layer had a thickness of 3 μm, and the polyethylene resin layer composed of linear low-density polyethylene had a thickness of 35 μm.

[0126] On the surface of the resin layer on the surface of the sealant layer, the PVD method was used, pressure: 3.0 × 10 -2 An aluminum vapor deposition film having a thickness of 30 nm was formed at 100 MPa.

[0127] The substrate and the surface of the sealant layer on which the vapor-deposited film was formed were laminated via a two-component curing urethane adhesive (Ru-77T / H-7, manufactured by Rock Paint Co., Ltd.) to obtain a laminate of the present invention. The polyethylene content in the laminate is summarized in Table 1. The laminates obtained in the following Examples and Comparative Examples and the polyethylene content in the laminates are also summarized in Table 1.

[0128] Example 1-2 High density polyethylene (ExxonMobil, HTA108, density: 0.961 g / cm 3 , melting point: 135°C) Medium density polyethylene (Dow Chemical, Elite 5538, density: 0.941 g / cm 3 , melting point: 129°C) and High density polyethylene (ExxonMobil, HTA108, density: 0.961 g / cm 3 , melting point: 135°C) The mixture was co-extruded by inflation molding, and then stretched 5 times in the machine direction (MD) using a stretching device to produce a substrate. In the substrate thus obtained, the layer made of high density polyethylene had a thickness of 5 μm, the layer made of medium density polyethylene had a thickness of 15 μm, and the layer made of high density polyethylene had a thickness of 5 μm.

[0129] A laminate was produced in the same manner as in Example 1-1, except that the substrate was changed to a substrate having a three-layer structure produced as described above.

[0130] Examples 1-3 High density polyethylene (ExxonMobil, HTA108, density: 0.961 g / cm 3 , melting point: 135°C) High density polyethylene (ExxonMobil, HTA108, density: 0.961 g / cm 3 , melting point: 135°C) and medium density polyethylene (Dow Chemical, Elite 5538, density: 0.941 g / cm 3 A blend resin containing 4:6 by mass of 1,2-difluorophenyl ether (melting point: 129°C) and 1,2-difluorophenyl ether (melting point: 129°C), Medium density polyethylene (Dow Chemical, Elite 5538, density: 0.941 g / cm 3 , melting point: 129°C) and Ultra-low density polyethylene (Dow Chemical, Affinity EG8100G, density: 0.870 g / cm 3 , melting point: 55°C) and The resulting mixture was extruded by inflation molding into a tubular film having, from the outside, a layer composed of high-density polyethylene, a layer composed of the blended resin, a layer composed of medium-density polyethylene, and a layer composed of very-low-density polyethylene, and the inner layers composed of very-low-density polyethylene were pressed together using a rubber roll. The film thus obtained had a layer composed of high density polyethylene, a layer composed of the blend resin, a layer composed of medium density polyethylene, a layer composed of very low density polyethylene, a layer composed of medium density polyethylene, a layer composed of the blend resin, and a layer composed of high density polyethylene.

[0131] The film obtained as described above was stretched 5 times in the machine direction (MD direction) by a stretching device to prepare a substrate. In the film thus obtained, the layer composed of high-density polyethylene had a thickness of 2.5 μm, the layer composed of the blend resin had a thickness of 2.5 μm, the layer composed of the medium-density polyethylene had a thickness of 6.25 μm, the layer composed of the very-low-density polyethylene had a thickness of 2.5 μm, the layer composed of the medium-density polyethylene had a thickness of 6.25 μm, the layer composed of the blend resin had a thickness of 2.5 μm, and the layer composed of the high-density polyethylene had a thickness of 2.5 μm.

[0132] A laminate was produced in the same manner as in Example 1-1, except that the substrate was changed to a substrate having a seven-layer structure produced as described above.

[0133] Examples 1-4 The ethylene vinyl alcohol copolymer was mixed with polyamide (Ube Industries, Ltd., 5033, melting point: 196°C, density: 1.14 g / cm 3 A sealant layer was prepared in the same manner as in Example 1-1, except that the above-mentioned step was changed to the above-mentioned step. In the sealant layer thus obtained, the surface resin layer made of polyamide had a thickness of 2 μm, the adhesive resin layer had a thickness of 3 μm, and the polyethylene resin layer made of medium density polyethylene had a thickness of 35 μm.

[0134] A laminate was produced in the same manner as in Example 1-1, except that the sealant layer was changed to the sealant layer produced as described above.

[0135] Examples 1-5 Ethylene-vinyl alcohol copolymer (Kuraray Co., Ltd., EVAL E171B, melting point: 165°C, density: 1.14g / cm 3 )and, Adhesive resin (Mitsui Chemicals, Inc., Admer NF557) Linear low-density polyethylene (Prime Polymer, SP1520, density: 0.913 g / cm 3 , melting point: 116°C) and a compatibilizer (Dow Chemical, maleic anhydride polyethylene, Retain 3000, density: 0.87g / cm 3 ) on a mass basis, a blend resin containing 8:2, Linear density polyethylene (Prime Polymer, SP1520, density: 0.913 g / cm 3 , melting point: 116°C) and The mixture was coextruded by the T-die method to form a sealant layer. In the sealant layer thus obtained, the surface resin layer composed of an ethylene-vinyl alcohol copolymer had a thickness of 2 μm, the adhesive resin layer had a thickness of 3 μm, the second polyethylene resin layer composed of a blended resin had a thickness of 15 μm, and the first polyethylene resin layer composed of a linear low-density polyethylene had a thickness of 20 μm.

[0136] A laminate was produced in the same manner as in Example 1-1, except that the sealant layer was changed to the sealant layer produced as described above.

[0137] Examples 1-6 The ethylene vinyl alcohol copolymer was mixed with polyamide (Ube Industries, Ltd., 5033, melting point: 196°C, density: 1.14 g / cm 3 A sealant layer was prepared in the same manner as in Example 1-5, except that the above-mentioned step was changed to the above-mentioned step. In the sealant layer thus obtained, the surface resin layer composed of polyamide had a thickness of 2 μm, the adhesive resin layer had a thickness of 3 μm, the second polyethylene resin layer composed of the blend resin had a thickness of 10 μm, and the first polyethylene resin layer composed of medium-density polyethylene had a thickness of 10 μm.

[0138] A laminate was produced in the same manner as in Example 1-1, except that the sealant layer was changed to the sealant layer produced as described above.

[0139] Comparative Example 1-1 Linear density polyethylene (Prime Polymer, SP1520, density: 0.913 g / cm 3 A single layer of unstretched polyethylene film was produced by extrusion molding using the polyethylene terephthalate (melting point: 116°C).

[0140] A laminate was produced in the same manner as in Example 1-1, except that the sealant layer was changed to the unstretched polyethylene film produced as described above.

[0141] Example 2-1 A laminate of the present invention was produced in the same manner as in Example 1-1, except that the aluminum vapor deposition film was changed to an aluminum oxide (alumina) vapor deposition film having a thickness of 20 nm formed by a PVD method.

[0142] Example 2-2 A laminate of the present invention was produced in the same manner as in Example 1-2, except that the aluminum vapor deposition film was changed to an aluminum oxide (alumina) vapor deposition film having a thickness of 20 nm formed by a PVD method.

[0143] Example 2-3 A laminate of the present invention was produced in the same manner as in Example 1-3, except that the aluminum vapor deposition film was changed to an aluminum oxide (alumina) vapor deposition film having a thickness of 20 nm formed by a PVD method.

[0144] Examples 2-4 A laminate of the present invention was produced in the same manner as in Example 1-4, except that the aluminum vapor deposition film was changed to an aluminum oxide (alumina) vapor deposition film having a thickness of 20 nm formed by a PVD method.

[0145] Examples 2-5 A laminate of the present invention was produced in the same manner as in Example 1-5, except that the aluminum vapor deposition film was changed to an aluminum oxide (alumina) vapor deposition film having a thickness of 20 nm formed by a PVD method.

[0146] Examples 2-6 A laminate of the present invention was produced in the same manner as in Example 1-6, except that the aluminum vapor deposition film was changed to an aluminum oxide (alumina) vapor deposition film having a thickness of 20 nm formed by a PVD method.

[0147] Comparative Example 2-1 A laminate was produced in the same manner as in Comparative Example 1-1, except that the aluminum vapor deposition film was changed to an aluminum oxide (alumina) vapor deposition film having a thickness of 20 nm formed by a PVD method.

[0148] <<Gas barrier property evaluation>> The laminates obtained in the examples and comparative examples and the oxygen permeability (cc / m 2 ·day·atm) and water vapor transmission rate (g / m 2 ·day) was measured by the following method, and the results are summarized in Table 1.

[0149] [Oxygen permeability] Using an oxygen permeability measuring device (OX-TRAN2 / 20 manufactured by MOCON), the test piece was set so that the substrate surface was the oxygen supply side, and the oxygen permeability was measured in an environment of 23°C and a relative humidity of 90% RH in accordance with JIS K 7126. [Water vapor permeability] Using a water vapor transmission rate measuring device (MOCON, PERMATRAN-w 3 / 33), the test piece was set so that the substrate surface was the water vapor supply side, and the water vapor transmission rate was measured in an environment of 40°C and relative humidity of 90% RH in accordance with JIS K 7129.

[0150] <<Laminate strength test>> The laminates obtained in the above Examples and Comparative Examples and the samples obtained by cutting the laminates into 15 mm-wide strips were measured for lamination strength (N / 15 mm) between the vapor-deposited film and the surface resin layer (Examples) and between the vapor-deposited film and the polyethylene film (Comparative Examples) using a tensile tester (Tensilon universal material testing machine, manufactured by Orientec Co., Ltd.) in accordance with JIS K6854-2, using 90° peeling (T-peel method) at a peeling speed of 50 mm / min. The measurement results are summarized in Table 1.

[0151] [Table 1] [Explanation of symbols]

[0152] 10: laminate, 11: substrate, 12: vapor deposition film, 13: sealant layer, 14: surface resin layer, 15: polyethylene resin layer, 16: adhesive resin layer, 20: packaging bag, 30: standing pouch, 41: easy-opening means, 42: notch portion, 43: half-cut line, 51: extraction nozzle portion, 52: curved portion, 53: cut-out portion, 60: laminated tube, 61: laminated tube body, 62: head portion, 63: body portion, 64: shoulder portion, 65: spout portion, 66: cap, 67: threaded portion, 68: welded portion, 69: bottom seal portion

Claims

1. A laminate including at least a substrate, a vapor-deposited film, and a sealant layer, the sealant layer comprises a surface resin layer and a polyethylene resin layer, The substrate is made of a polyethylene resin, the surface resin layer of the sealant layer contains a resin material having a melting point of 150° C. or higher, the polyethylene resin layer of the sealant layer has a multi-layer structure including at least one layer containing a compatibilizer; the vapor-deposited film is provided on a surface resin layer of the sealant layer, The content of polyethylene resin in the entire laminate is 80% by mass or more. Laminate.

2. The laminate according to claim 1 , wherein the surface resin layer contains a resin material having a melting point of 150° C. or higher and 265° C. or lower.

3. A laminate as described in claim 1 or 2, wherein the melting point difference between the polyethylene resin contained in the polyethylene resin layer of the sealant layer and the resin material having a melting point of 150°C or more contained in the surface resin layer is 20 to 80°C.

4. 4. The laminate according to claim 1, wherein the resin material of the surface resin layer is made of a polymer having a polar group.

5. The laminate according to any one of claims 1 to 4, wherein the resin material of the surface resin layer is one or more resin materials selected from ethylene vinyl alcohol copolymer, polyvinyl alcohol, polyester, nylon 6, nylon 6,6, nylon 6-nylon 6,6 copolymer, MXD nylon, and amorphous nylon.

6. The laminate according to any one of claims 1 to 5, wherein the surface resin layer is provided so as to be in contact with a layer containing a compatibilizer of the polyethylene resin layer.

7. The laminate according to any one of claims 1 to 6, further comprising a barrier coat layer provided on the vapor-deposited film.

8. The laminate according to any one of claims 1 to 7, which is used for a packaging container.

9. A packaging container comprising the laminate according to any one of claims 1 to 8.

10. The packaging container according to claim 9, which is a packaging bag.

Images